Method of hydrating dolomitic or magnesian lime.



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CHARLES WARNER AN D IRVING WARNER, 0F WILMINGTGH, DELAWARE,

METHOD OF HYDRATING DOLOMITIC 01%. MAGNESIAN LIME.

Etc Drawing.

To all whom it may concern:

Be it known that we, (1) CHARLES WAR- nnn and (2) lnvrne l vARNER,citizens of the United States, residing atW ilmingtOn, in the county ofNew Castle and State of Delaware, have invented certain new and usefulimprovements in Methods of Hydrating Dolomitic or Magnesian Lime, ofwhich the following is a specification.

' Our invention relates to a process of hydrating dolomitic or magnesianquick-lime (by which is meant lime containing more than five per cent.of magnesium oxid) and has for itsobject to secure, as far as possible,the hydration of a material art or all cally satisfy the calcium oxidand amaterial proportion of the magnesium oxid. The heat of reactionproduced by the hydration of the lime, generates steam and under thecombined effect of the Water and steam under pressure, a material part(6. g. or even all the magnesia may be hydrated. The process may also becarried out in two stages, the first stage consisting in hydratinglthedolomitic or magnesian quick-lime, comminuted preferably to coarsepulverization, by the addition of only suificient Water to effect thehydration of the calcium oxid. This hydration is eflected preferably atatmospheric pressure and under such condi- Specificaticn of LettersEatent,

Application filed. July 10, 1914. Serial Ito, 850,226.

tions as to avoid any unnecessa rise in temperature, as the hydration olime at high temperature has a tendency to produce a crystallizedcondition which diminishes the plasticity oi'the mortar, while hydrationat low temperatures conduces to the production of a colloidal hydratewhich is plastic and freeworlring under the trowel. The second stage ofthe process consists in subjecting the lime-hydrated mixture, eitherimmediately or after a convenient interval to the further action ofwater and steam, by introducing the dolomitic hydrate into closed.vessels where the hydration of the magnesium oxid is efiected by furthercontact with Water, in the presence of steam, under a maintainedpressure. A material part of the magnesia of the dolomitic or magnesianquick-lime may be hydrated by the use of nominal or low pressuresv suchas from slightly above atmospheric pressure to 10 or 15 pounds; for thehydration of larger percentages of the magnesium oxid in limes of thischaracter, much higher pressures may be used.

We claim:

The process of hydrating magnesia-containing quick-lime which consistsin first adding Water suficient to hydrate the calcium oxid while atatmospheric pressure, and then efi'ecting the hydration of the magnesiumoxid in a closed vessel and under maintained pressure by further contactwith water. v

In testimony whereof, we afix our signatures in presence of twowitnesses.

CHARLES WARNER.

' v IRVING WARNER.

Witnesses:

W. C. SMITH, R. DINSMORE.

